The lead is automatically removed from our call queue when the rep’s phone and the lead’s phone are connected for 00:40 seconds or more. (This duration be adjusted but it works well because it leaves time to listen to a voice mail greeting and leave a voice mail without exceeding the time limit).
There are a few other ways to remove the lead from the queue;
Stop post from CRM or webpage
Press 3 prompt via S2L
S2L Active Calls Dashboard